From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0A4F43A0E88; Thu, 2 Jul 2026 16:29:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783009776; cv=none; b=ZQ1vD7dg19tOMTQsxWrcBHN9G0ecfU03sTbITzlUVtsKYM/XTebwI4UObJo9O1WBXv3LPx1eCPJ6vjnhQkEx/N/ZvGk61+5WhR7MnGcDHe3tIYLxX4jY5dXwAlT6wAP4t3SPS3h+/7TUYRQg3IsWCF7Y8caYpVCp6obq58FVQrM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783009776; c=relaxed/simple; bh=4i+rj+KEzXJ5xQW5kmOzvMVX7bqWVQ2EkHvxpXokWU8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Yi+JTMToT7MU3ET37bULxGVSBu7OPcEMOqdXulaUd0qpK4FGrscvvnOxchGAcaP7owUjkrppKE9QwSgFUfvomAS2p3XtCYiUhMFr4D8yLKbTqaNuinzOVTot/3L722Xxp49+vf+ldlr0nh2goV42lcAsCe/vOb1D6wHzEtrAP6E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=M41FvhQH; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="M41FvhQH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 475FD1F000E9; Thu, 2 Jul 2026 16:29:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1783009772; bh=ElT2ou2j4BzsOfvU8sqVFsjZsMU9DfkR+OnOnPtnNek=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=M41FvhQHvZ2cIq3ZpcGAhd7z8hs5JQNMe0yYAoMa/NMdPWFw1rsdh6kGPViISgoGI OTigMbMCA3TAQg9WNF3d/YuNIvTyHmx5jqcqcDVYJGEvkT2okIX0Prf2kde4PabRbn tQgQfBV3iWTH/C+6OcA0MRu8abd8wIinjW8uFNDk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, Sven Eckelmann , Sasha Levin Subject: [PATCH 5.15 45/95] batman-adv: tp_meter: annotate last_recv_time access with READ/WRITE_ONCE Date: Thu, 2 Jul 2026 18:19:48 +0200 Message-ID: <20260702155110.155330535@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260702155109.196223802@linuxfoundation.org> References: <20260702155109.196223802@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann commit d67c728f07fca2ee6ffdc6dd4421cf2e8691f4d1 upstream. The last_recv_time field for batadv_tp_receiver tracks the jiffies value of the most recent activity and is used to detect timeouts. These accesses are not consistently protected by a lock, so READ_ONCE/WRITE_ONCE must be used to prevent data races caused by compiler optimizations. Cc: stable@kernel.org Fixes: 33a3bb4a3345 ("batman-adv: throughput meter implementation") Signed-off-by: Sven Eckelmann Signed-off-by: Sasha Levin --- net/batman-adv/tp_meter.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/batman-adv/tp_meter.c b/net/batman-adv/tp_meter.c index 105cda5b0b2cda..503819e9839c62 100644 --- a/net/batman-adv/tp_meter.c +++ b/net/batman-adv/tp_meter.c @@ -1183,7 +1183,7 @@ static void batadv_tp_receiver_shutdown(struct timer_list *t) bat_priv = tp_vars->bat_priv; /* if there is recent activity rearm the timer */ - if (!batadv_has_timed_out(tp_vars->last_recv_time, + if (!batadv_has_timed_out(READ_ONCE(tp_vars->last_recv_time), BATADV_TP_RECV_TIMEOUT)) { /* reset the receiver shutdown timer */ batadv_tp_reset_receiver_timer(tp_vars); @@ -1424,7 +1424,7 @@ batadv_tp_init_recv(struct batadv_priv *bat_priv, tp_vars = batadv_tp_list_find_session(bat_priv, icmp->orig, icmp->session, BATADV_TP_RECEIVER); if (tp_vars) { - tp_vars->last_recv_time = jiffies; + WRITE_ONCE(tp_vars->last_recv_time, jiffies); goto out_unlock; } @@ -1455,7 +1455,7 @@ batadv_tp_init_recv(struct batadv_priv *bat_priv, kref_get(&tp_vars->refcount); timer_setup(&tp_vars->timer, batadv_tp_receiver_shutdown, 0); - tp_vars->last_recv_time = jiffies; + WRITE_ONCE(tp_vars->last_recv_time, jiffies); kref_get(&tp_vars->refcount); hlist_add_head_rcu(&tp_vars->list, &bat_priv->tp_list); @@ -1506,7 +1506,7 @@ static void batadv_tp_recv_msg(struct batadv_priv *bat_priv, goto out; } - tp_vars->last_recv_time = jiffies; + WRITE_ONCE(tp_vars->last_recv_time, jiffies); } /* if the packet is a duplicate, it may be the case that an ACK has been -- 2.53.0